There is a handful, quite easy to find 2nd hand spare, thanks alots for the advise, tot of making it more powerful.
-I have customise my stock air filter,cut away air reasonator. Remove the grill that is behind the logo, drill plenty of holes so air will flow in when I drive.
-Tension my throttle cable, grease my clutch cable, remove my gearknob & sock & grease inside.
-Pulling off the rubber tube that connect at the electronic vacuum regular.
-Replace with coolant in the radiator
-wonder is there still anything I can do to make it more powerful?

Yes that COE is very expensive. Is it the same price for vans? Have you got full use or just the weekend one with red number plates?
Quite honestly, any simple mods you make will yield very little power due to the design of the engine.
Those 1.9's were always a bit slow. You could use the 306/406 XUD 1.9 turbo engine for more power, or turn up up the fuelling on the pump, but you would fall foul of the Singapore emissions regs, and I'm not sure what the penalties are.
The turbo route is probably the best option.

It's under the cat c commercial vehicle, normal plate can use all day long, just renewed it for another 5 years. In sg, commercial vehicle can only use max 20 year including renewal Coe, after tat force to scrap, other countries like our vehicle very much cos mileage low as sg is a small countries. U mean my current mechanical fuel pump Lucas able to turn up? Almost cos higher idling right?

I don't mean turn up te idle, I mean fuel delivery. It will give a bit more power, but also black smoke.
Sg are tightening up on emmissions, I have been told they are fining people for leaving engines idling.
Taken to race levels it looks like this https://www.youtube.com/watch?v=7igsQBORSY8 so probably not viable in Sg.
Personally, I would go the XUD turbo route.

What part of Singapore are you from?

The following 1 user says Thank You to Col for this post:1 user says Thank You to Col for this post • malgpz900